The demonstration of an estrogen binding system in the pancreas of animals and the human has been followed in our laboratory by the characterization of the receptor, including its association constant, stability and specificity for estrogens, particularly estradiol-17 beta. Some purification of the receptor has been accomplished and antibodies developed to it. The latter have allowed us to demonstrate specific localization of estradiol-17 beta within the pancreas. In another approach, a number of biochemical and metabolic parameters have been determined following the administration of estrogens and these include: lipase, DNAse and amylase activity, the levels of various ions (K ion, Na ion, Ca ions) and the concentration of zinc and bicarbonate. Once a sensitive parameter is established, the in vitro behavior of this parameter upon incubation of pancreatic microsomes from estrogens stimulated and unstimulated animals will be determined as a means of further elucidating the possible role of the estrogen - receptor complex in pancreatic physiology and pathology. The presence or absence of the estrogen receptor in cancers of the pancreas is being studied in our laboratory, the data to be correlated with the clinical, histologic and therapeutic aspects of each cancer. The aim of this approach is to develop a therapeutic index for cancer of the pancreas, akin to that in cancer of the breast.